High-grade digital microscopes encompass a stationary stand body with which the microscope is mounted its placement surface, and a unit, pivotable relative to the stand body around a rotation axis, in which, in particular, the image sensing unit of the digital microscope and an objective system are arranged. The purpose of this pivoting is in particular to allow the objects to be observed from different viewing angles; this can be advantageous in particular for the assessment of depth information.
If the pivot unit is arranged so that the pivot unit is arranged uprightly above the stage, and the gravity vertical thus extends through the rotation axis of the pivot unit, i.e. the longitudinal axis of the shaft, then no torque acts on the pivot unit and the pivot unit would remain in its position even without a brake unit. When the pivot unit is pivoted out of that position, however, the weight of the pivot unit produces a torque, directed around the rotation axis of the pivot unit, whose magnitude increases as the pivot unit is pivoted farther out of the perpendicular position, since the tangential component of the weight that generates the torque becomes that much greater.
In known digital microscopes this torque is absorbed by the brake unit. This has the disadvantage that upon release of the brake unit in order to modify the position of the pivot unit, this torque must be applied by the operator. If he or she neglects this, uncontrolled movement of the pivot unit can occur, which can result in damage to the microscope or in property damage or personal harm. It furthermore has the disadvantage that the brake unit must be correspondingly dimensioned so that it can reliably hold the pivot unit in position even at its maximum deflection. This requires sufficiently large and thus space-intensively dimensioned brake units.